Angle plate for grinding tool bits



Se t. 14, 1954 R. J. AULENBACH 2,688,828

ANGLE PLATE FOR GRINDING TOOL BITS Filed Sept. 5, 1951 IN V EN TOR.

Patented Sept. 14, 1954 UNITED STATES PATENT OFFICE ANGLE PLATE FORGRINDING TOOL BITS Richard J. Aulenbach, Watertown, Mass. ApplicationSeptember 5, 1951, Serial No. 245,237

3 Claims. 1

This invention relates to an angle positioning device for tool grinding.

One object of my invention is to provide a simple and relativelyinexpensive device for positioning a tool accurately, ready to grind itor the tool bit, so that back clearance can be obtained simultaneouslywith side clearance.

Another object is to provide a base for the above device having aplurality of side surfaces that slant outwardly at different angles,greater than a right angle, to the bottom surface.

The foregoing and other objects which will appear as the nature of theinvention is better understood, may be accomplished by a construction,combination and arrangement of parts such as is disclosed by thedrawings. The nature of the invention is such as to render itsusceptible to various changes and modifications, and, therefore, I amnot to be limited to the construction disclosed by the drawings nor tothe particular parts described in the specification; but am entitled toall such changes therefrom as fall within the scope of my claims.

In the drawings:

Figure 1 is a front elevational view of my angle positioning device.

Figure 2 is a side elevational view thereof.

Figure 3 is a fragmentary, front elevational view thereof, showing atool bit in a position ready for grinding.

Figure 4 is a view similar to Figure 3; but showing the tool bit inanother position.

Figure 5 is a view similar to Figure 3; but showing the tool bit inanother position.

Figure 6 is a top plan view of the base plate of my device.

As illustrated, my positioning device has a base plate I having aplurality of side surfaces, each preferably being at a different anglewith relation to the bottom surface H. For example, the side surface [2is ground to an angle of 3 degrees thereto, the side surface M to one ofdegrees, the side surface Hi to one of 7 degrees, and the side surfacel8 to one of 9 degrees. This enables, the user, in grinding to obtainside clearance on the tool or tool bit being ground, to the extentdesired.

An upstanding plate 24, when assembled, is adapted to bear against anyone of the said base plate side surfaces, and to be fastened to saidbase plate ID by set screws 26 which extend through holes 28 in saidupstanding plate 24 and into threaded holes 30 in said base plate It,thus removably holding the upstanding and base plates together. Saidupstanding plate 24 2 has a vertically extending surface, hence theangle at which it extends is varied by the angle of the side surface ofthe base plate adjoining it. The bottom surface 32 of said upstandingplate 24 extends angularly upward from said base plate ill to permitchanges in the angle at which it may extend upwardly.

A plurality of holes 34 are provided in said upstanding plate 24 in anouter or border portion thereof at varying angles with respect to acenter hole 36 therein. In use, a dowel pin 3'! is inserted firmly insaid center hole 36 and another pin 38 is inserted in a said border hole34,. thus establishing an angular relationship between the two pins 31and 38 whereby to accurately position a tool for grinding by laying itagainst the dowel pins.

In order to obtain angles to finer degrees I provide spacers of varioussizes, the smaller being given the numeral 40, a larger or medium one,is given 42 and the largest is given 44. These preferably have a holethrough the center hence they fit over said center dowel pin 31 and arehandily available for use. They are held, when not in use, by a screw 48that extends through the spacer holes and into a screw-threaded hole 50in said base plate [0. To establish the desired angle between a saidcenter hole 36 and a border hole 34 a spacer of the correct size isplaced on a said dowel pin 38. Additional spacers, of different sizescould be provided as needed.

To correctly position a tool T for grinding it, said tool is placed onsaid center dowel pin 31 and on a spacer which is set over the dowel pin38 set in a border hole. Which one of said holes 34 said pin 33 is setinto, and which spacer is thereafter placed over said pin 38, dependsupon the angle it is desired to establish between the center pin 31 andthe spacer. Of course, it is possible in some instances, to establishthe desired angle between said center pin 31 and a pin 38 in a said hole34 without the use of a spacer.

When the tool is correctly positioned, as illustrated, by said Figures3, 4 and 5, a well known parallel clamp, indicated by C, firmly clampsit to said upstanding plate 24 and the tool bit is now ready forgrinding.

To change the angle of said upstanding plate 24 said screws 26 areremoved and another surface of the base plate [0 is presented to saidupstanding plate 24. If, for instance, an angle of 9 degrees relative tovertical is desired, said base plate surface I8 is presented againstsaid upstanding plate 24.

I claim:

1. An angle positioning device for tool grinding comprising a base platehaving a side surface extending upwardly at an obtuse angle to thebottom surface, and an upstanding plate having a side surface extendingupwardly and adjoining said base plate side surface and extending at anobtuse angle with relation to the bottom surface of said upstanding,plate, said base plate hayingjafcentrali hole therein and a plurality ofholes at a border portion thereof, said holes being adapted to receivepins, and means attaching said base plate and upstanding plate together.

2. An angle positioning device for tool grinding comprising a base platehaving an angularly disposed side edge and an"upstandif1g' plate"adjoining and extending at an obtuse angle to said base plate, meansattaching said plates together, said upstanding plate having a centralhole therein anda plurality oiother holes therein spaced radially fromsaid central hole, a'pin in said central hole and'a pin'in'one of saidother holes, and a spacer having a hole therethrough extending over saidpin in a'said other hole.

3. An angle positioning device for tool grinding comprising a base platehaving a plurality of side surfaces extending upwardly at differingobtuse angles to the bottom surface, and an upstanding plate having aside surface adapted to adjoin and extend upwardly and form an obtuseangle with any of said base plate side surfaces, said upstanding platehaving a central hole therein and a plurality of holes adjacent a borderportion thereof, said holes'being adapted to receive pins, and means toattach said base plate and upstanding plate together.

Referemesoicea in the file of this patent UNITED STATES PATENTS NumberName Date 1,047,424 Lumsden Dec. 1'7, 1912 1,304,070 Lenz May 20, 19191,324,681 McDonald Dec. 9, 1919 2,324,025 Revell July 13, 1943 2,324,476Becker July 20, 1943 2,366,385 Comfort Jan. 2, 1945 2,385,396 Baum Sept.25, 1945

